PART 1 The following is the current simplex tableau of a linear programming problem. The objective is to minimize -2x4 - x5 2x6, and x1, X2, and x3 are the slack variables. Row X1 X2 X3 X4 X5 6 RHS b -42 X6 -14 1 X2 4 5 3 X4 2 (a) Find the values of the unknowns a through h in the tableau. [10 points] (b) Find B-1. [5 points] (c) Is the tableau optimal? [5 points]